Hi,
I've been trying both ways for both onchange and onconfirm like this:
set mytextfield:onchange to {parameter s. print s.}.
or:

function mytextfieldchanged {parameter s. print s.}
set mytextfield:onchange to mytextfieldchanged@.

(... same for onconfirm)
and that does nothing ... It works well for buttons like this:
set mybutton:onclick to {print "b1 clicked".}.

LKS
PS: KSP 1.8.1, KOS 1:1.2.1.0